Phrase Meaning – ‘A Sore Throat’ vs ‘A Strep Throat’ vs ‘Strep Throat’

If my throat is red and it feels painful to swallow, I say

I have a sore throat.

Recently, I've come across "strep throat". It's an infection and it doesn't seem to be used interchangeably with "sore throat". And I am wondering why.

I have a throat infection.

If it's a type of infection, why can't I say the following?

I have a strep throat.

I have a strep.

All the sentences I've found suggest leaving out the article.

I have strep throat.

I have strep.

Most likely, your doctor will prescribe an oral antibiotic if you have a strep infection.

If you have a strep infection, your health care provider will prescribe an antibiotic.

Could you demystify it for me?

The difference between "sore throat" and "strep throat".
Whether I should use an indefinite article before "strep throat".

Best Answer

There's little consistency in the articles we use (or don't use) with names of illnesses.

Ex:

I have a cold
I have the flu
I have diarrhea

Strep or strep throat is one of the many illnesses that do not get an article:

I have strep/strep throat

But this is only true when we're using strep as the name of a condition. It's also the name of a bacterium - actually, the name of the bacterium is streptococcus, but it's occasionally shortened to strep. When we're talking about the bacteria, as opposed to the illness caused by the bacteria, we use articles as per normal:

The streptococcus bacteria were hard to find.
A streptococcus bacterium can be oxidase-negative.